Classes of lipids in milk

Species Phosphatidyl- choline Phosphatidyl- ethanolamine Phosphatidyl- serine Phosphatidyl- inositol Sphingomyelin Lysophospho- lipids  

Product Total lipid (%, w/v) Phospholipids (%, w/v) Phospholipid as %, w/w, of total lipids 

Cholesterol (Appendix 3C) is the principal sterol in milk ( 95% of total sterols) the level ( 0.3%, w/w, of total lipids) is low compared with many other foods. Most of the cholesterol is in the free form, with less than 10% as cholesteryl esters. Several other sterols, including steroid hormones, occur at trace levels. 

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